The act of suffocating a gopher between two bodies (preferably one male and one female) mid-coitus and once said rodent has expired, shaving the sucker clean. The gopher is subsequently ejaculated on, covered in the jizz and rolled in freshly powdered cocaine. Finally the female is sodomized with the gopher.

"Yo girl! What be that white stuff on your legs?"
"Oh. That just be some nose candy. My mac daddy gave me the ol' Powdered Donut last night. I really like it."

After having been at a race/outdoor concert/hunting/other event where you have not showered for several days and your gear begins to get funky you apply baby powder to the front and back. Then you find a willing partner to eat your ass resulting in a ring resembling a powdered donut on their mouth.

Friend 1: Man that was a great race but I'm ready for a shower.
Friend 2: Hell yeah I found some skank to toss me off and left her with a powdered donut.